Soldering machine



H.O.BOEHME S OLDERING MACHI NE Filed March 23. 1921 2 Sheets-Sheet 1 O 1A 5 i JAKATTOR/A/EYS Dec. 25 1923.

H. O. BOEHME SOLDERING MACHINE Filed Marh 25. 1921 O W/TA/ESSEJ 2Sheets-Sheet 2 IAIVENTOR Patented Dec..- 25, id.

BEAN O. BOEEME, OF NEW YORK, N. Y.

SOLDING MACHINE.

Application filed march 23, 1921.

lustrated in the accompanying drawings,

- the particular novel features of my invenafter it has left tion beingmore fully pointed out in the annexed claims.

My invention relates to mechanism and means for soldering articles toeach other in continuous succession for quantity production, whereabsolute uniformity of the soldered joints is required.

My improved machine is of particular advantage in cases where smallarticles are being soldered to each otherwhich are awkward to handleduring the soldering process and-which therefore are apt to becomeunevenly soldered, be it to uneven depth or be it due to unevenness attheedges where freguently fringes or ridges of solder are likely tooccur.

I have shown my improved machine as particularly applied to solderingcurved ribbon Contact brushes such as are used for delicate electricinstruments and apparatus, without thereby, however, limiting the scopewithin which the device shown may be employed for the same or similarpurposes in connection with articles other than ribbon brushes.

In examples of the kind. illustrated it is required that two or moresimilarly curved ribbon elements are soldered together at one end to adefinite depth in such manner that the soldering becomes solid thruoutwithout thereby increasing the total thickness of the brushes andwithout forming fringes or ridges of solder at the ends of the brushes.1 have found that this object can be attained by caretul heating of theportions to be soldered, and by controlling carefully the amount ofsolder supplied and by exposing the joint for a certain length of timeto a suitable temperature the solder supply mean? to permit uniformdistribution of the so der over the entire portion to be soldered.

In the drawings,

Fig. 1 is a plan view of the entire soldering device;

Fig. 2 is a detail perspective View in larger scale at one of thegrippers;

' thence past the soldering device,

Serial No. 45%,899.

transverse section thru the de- Fig. 3 is a Fig. 1 on the line 3-3 inthat vice shown in figure;

Fig. 4 is a side elevation partly in section of the fiux supply device,in larger scale;

Fig. 5 is a vertical section through the soldering device on the line5-5 in Fig. 3, but in larger scale;

Fig. 6 is a detail view, partly in vertical section of the grippersupport taken on line 66 Figure 3;

Fig. 7 shows gripper in open position in larger and Fig. 8 shows inished brush.

The underlying idea involved in my machine is to provide a constantlymoving conveye'r element such as a wheel or endless belt or the like,provided with means for attaching to it grippers into which the articlesto be soldered are placed, which grippers are then moved first past aflux supply device, thereafter past a preheating device and whereafterthey can be removed from the conveyor by the operator and replaced byothers charged with new articles to be soldered.

In Figs. 1 and 3, l have illustrated a large wheel 1, as the conveyor.lhis wheel is horizontally placed above an operating table 2 andoperated from asuitable source of power (not shown) by means of belt 3and pulley ll. In order to insure proper alinement of the wheel inparallel to the operating table 2, the lower rim of the wheel issupported by a number oi rollers 5 mounted on the table, of'which twoare shown in Fig. 3. Thus any accidental vertical pressure on the wheelrim which may be exerted during the insertion or removal of the gripperscannot impair the horizontal 'alinement of the wheel.

At the upper periphery of wheel 1 are provided a number of gripperholders 6, preferably placed equidistant from each other and which areslotted vertically as shown in Fig. 6 in detail, such that member 7 ofgripper 8, provided with a similar vertical slot 7 at its lower edge maybe inserted therein. For the purpose of this machine, to be explainedlater, it is necessary that the ippers 8, should have a slight verticaltilting motion on their supports 6, which is brought about by incliningthe bottom of the s 0t in supports 6 downwardly towards the forwardportion of the 7 perspective view a finthe outside as is shown in F 3,and by making the slot 7 in the gripper member 7 slightly wider than thethickness of sup-' port 6 so that member 7, as it were, hangs on theupper edge 6 of the inclined bottom of holder 6. Thus I am enabled toslightly lift the heads of the grippers without dislod ging them fromtheir supports, the grippers falling back to their normal position bythe heavier weight of their outer portions after they come out ofcontact with the lifting means described hereafter. At the same time thegrippers remain easily removable, by lifting them out of the holders.

The grippers 8 are shaped particularly to hold the curved. brushelements for which the present machine isspecifically designed. As maybe seen from Fig. 8 the finished brush 9 consists in this instanceof'two constituent portions a and b of like curvature, nested into eachother. They are soldered together at one. of their ends as shown at c inFig. 8, and the requirement is that the solder be solid throughout theentire contact area 0 without forming fringes or ridges at the edges. Asshown in Fig. 7 member 10 of the gripper is provided near its outer endwith a curved block 11 formed to the cur vature of the brush and of thesame thickness as the width of the brush. Member 7 of the gripper,pivotally attached to member 10, is complementary shaped so that whenthe gripper is closed as shown in F ig. 2 the two constituent brushelements a and b are held tightly together. A stopping pin 12 isprovided on block 11, so as to position the two brush elements a and bwhen inserted into the gripper such, that only slightly more than theportion 0 to be soldered protrudes beyond the gripper as shown in Figs.2 and 7. It is advisable that the protruding portion be slightly largerthan the brush portion a to be soldered together, for reasons to beexplained later on. The two members 7 and 10 of the gripper are pivotedto each other at-such points that the large rearward extension of member10 will always tend to close the gripper as shown in Fig. 2.

The conveyor wheel 1 rotates in the direction of the arrow in Fig. 1.and the flux supply device 20 and the soldering device 21 are mounted onthe operating table 2 in the path of the brush ends a so that thegrippers first encounter the flux supply 20 and then the solderingdevice 21.

The flux supply device 20 consists of a support 22 on which the fluxcontainer 23 is positioned at such. height that when it is filled withflux 24 to the level shown the brush ends a will be immersed therein asshown in Fig. 4. In order to lift the gripper heads and brush ends overthe edges of fiux container 23, a guide frame 25 is provided on support22, which stands in the line of travel of the lower edge 26 of gripperblocks 11, so that when the grippers 8 travel past the flux supply inthe direction shown in Fig. 4, they encounter the inclined contour ofguide 25 whereby theyarelifted over the edge of the container 23 afterwhich they are allowed to drop again until edge 26 comes into contactwith the container edge, which allows the brush end 0 to remain immersedwhile the gripper passes along the container, whereafter they are liftedout again overthe edge of the container by a similarly inclined portionof guide 25. In order to prevent an undue amount of flux to adhere tothe brush ends when they emerge from the flux, a stripper in the form ofa spring, 27, fastened to the container bottom is provided, over whichthe brush ends 0 must travel before, or at about the time, when they arelifted out of the flux, by which the excessive amount of flux is removedand allowed to flow back into the container. The proper height of guide25 may be adjusted as shown at 28.

The soldering device 21 consists of a con- I tainer 29 shown in detailin vertical section in Fig. 5 and also in Fig. 3, which may consist ofany suitable good heat conductor, preferably copper. Within the hollowportion of this container is mounted a metal roller 31, preferably ofcopper, on a shaft 32 journalled in the container walls, and at one endof which is fixed sprocket wheel 33.

The container is filled with solder 30 which is kept liquid and at theproper temperature by means of a Bunsen burner 34 or other suitablemeans. The roller 31 is mounted in the container at such height that aportion of its periphery protrudes beyond the upper edge of thecontainer, the whole device being mounted on a bracket 35 secured to theoperating table 2 and the container being adjustable on the bracket asto height by means of adjusting screw 36. An asbestos wall 37 ispreferably placed between the bracket and the/heat supply 34 to shieldthe former from the flames. The soldering device is placed into the lineof travel of the brush ends 0 so that these ends must pass over roller31, adjacent to which an ad ustable guide 38 is provided o'n container29 for thepurpose of lifting grippers 8 to the desired height beforethey encounter roller 31, so that the corners of the brush endsencounter and leave the roller at a definite point of its periphery, andso that the brush edge remains in contact with the roller throughout adefinite angle, for instance angle 6 (Fig. 5). As soon as the individualgrippers 8 have passed the roller they slide down the other end of theguide 38 and assume their normal level, at which they ordinarily travelwith conveyer wheel 1. It is essential that the peripheral speed ofroller 31 should have a definite relation to the speed at which brushends 0 travel past the brush ends a travel.

soldering device. This relation depends upon the consistency of thesolder and on the amount to be applied to the jomt. I have found that inorder to obtain a perfect joint it is not suflieient that the brush ends0, when encountering roller 31, rotate the latter so that adheringsolder is sup lied to the brush ends. In fact it would he a disadvantageto cause the brush ends 0, as itwere, to operate the roller, becausethereby they would always pick up too much solder, with the result thatsmall ridges of solder are formed on the outside of the brush edges,which is detrimental for the purpose for which the brushes are used. Inorder to avoid this disadvantage I rotate roller 31 in the direction ofthe arrow positively by outside means, such as are shown for instance inFi 1. As will be seen from this figure, sproc et wheel 33 mounted on theshaft 32 of roller 31 as described before, is operated thru sprocketwheel connected to a worm gear drive 41 operated by a small motor 42.The speed of this motor and aforementioned worm gear 41 are chosen sothat the desired relation between the roller speed and the brush speedis obtained.

This positive drive of the solder supply roller has the furtheradvantage that this roller continuously moves, so long as the device isoperated, and thus also rotates intermediate the time at which twosuccessive grippers pass the roller. This continuous rotation has theadvantage that continuously fresh solder is picked up by the roller fromthe liquid supply 30 whereby the film of solder on the roller remains ofsubstantially uniform thickness and quality.

In order to obtain a perfect solder joint the heat supplied tothe brushends 0 solder supply roller is not sufficient. it necessary and ofadvantage to not only preheat the brush ends before they reach thesoldering device but to also supply an additional amount of heatdirectly to the brush ends during the soldering process and subsequentlythereto. To attain this purpose I have provided the following heatingmeans:

Between the flux supply 20 and the soldering device 21, as illustratedin Fig. 1, is disposed a Bunsen burner 45 which is horizontally disposedand closed at its end. A number of small holes 46 are provided in thecylindrical surface of burner 45, preferably in line with the circularpath along which These holes are comparatively small so that only smallflames will emanate therefrom, and the Bunsen burner 45 is adjusted asufficient distance below the brushes to only heat them to the desireddegree. For the purpose of such adjustment the burner 45 is attached toa bracket -17 which in' turn is fastened .to

chain drive 39 from a' bracket 35 which carries the solder supplydevice. Burner 45' extends sufficiently close to the soldering device 21so that the brushes encounter the soldering roller almost immediatelyafter they have passed the burner.

In addition to this preheating device I provide a second Bunsen burner48 fastened on an adjustable bracket 49. The mouth 50 of this burner. isflattened out so that a broad flame will emanate therefrom, which ishorizontally adjusted so that the broad flame fills the gap betweenburner 45 and the solderin device 21, and besides plays over the sol ersupply roller 31 and somewhat beyond. Thus when the brush ends a havepassed burner 45 they remain exposed to a suitable heat before the reachthe solder roller 31 and during t e soldering process and also for ahave left the soldering roller. This. arrangement I find insures aperfect soldered joint of uniform quality wit out containing an excessamount of solder which might unduly increase the thickness of the brushelements at the joint, and without producin fringes or ridges of solderat the brus edges.

It has been previously stated that the brush portions 0 to be joinedprotrude slightly more than their own length beyond the grippers. Thepurpose of this expedient is to permit the solder to fiow up the'desireddepth into the joint. beyond which however the solder cannot flow,because the heat supplied to the brush ends is quickly absorbed by theheavy metal grippers.

After the brushes have left the soldering device, an operative nowremoves the grippers from the transporting wheel 1 and then removes thefinished brush therefrom. whereafter he may recharge the gripper with anew pair of unsoldered brush elements.

I claim 1. A machine for automatically soldering articles together,comprising flux applying meansadapted to supply flux to the articles, asoldering device for supplying solder to said articles, gripping meansfor holding the articles in position relatively to each other andconveying means adapted to receive the gripping means and to carry themto the flux and soldering applying means, and means for heating thearticles on their way to the soldering means and during the solderingoperation, said gripping means having suitable shape and suflicient heatconductivity to keep those portions-of the articles chilled on which nosolder is desired- 2. In a soldering machine of the character describedgrippers for holding articles to be soldered in relative position toeach other, said grippers consistmg each of two members, pivotallyattached to each other and shaped at their ends to fit the contour shorttime after they IOU iis

. of the articles, the free ends of said members to each other, grippersconsisting each of.

two members pivotally attached to each other, one member having at itsend a block correspondingly curved. to support said elements, the othermember being of complementary shape to hold said elements on theirsupport and to remain in tight contact with them when the gripper isclosed, the free ends of said members being of suitable length to causeone member by its Weight to close the gripper when thefree end of theother member is supported, a stop on one of said members for determiningthe length which the elements protrude beyond the gripper head, fluxsupply means, soldering means and conveying means, the latter beingadapted to pivotally and removably support one of said gripper membersand to carry the gripper heads past said flux and solder supply means.

4. In a machine for soldering articles together, grippers for holdingthe articles in soldering position, a conveyer for supporting andconveying said grippers in a prescribed path and a solder applyingdevice located in the path of the articles, said device comprising asolder container, a roller 'journalled therein and protruding with aportion of its periphery be 0nd the container edge,'means for retatingsaid roller continually means for heating said container and means forguiding said grippers over said roller in the direction in which theroller periphery moves and at a suitable speed relatively to the rollerspeed to cause the articles contained therein to remain in contact withsaid roller over a predeter- 7 mined length of its periphery, and topick up only the amount'of solder which may be held between the articleportions to be joined.

5. In a machine for soldering articles together, grippers for holdingthe articles in soldering position, a conveyer for supporting andconveying said grippers in a prescribed path and a solder applyingdevice located in the path of the articles, said device comprising asolder container, a roller journalled therein and protruding with aportion of its periphery beyond the container edge,means for rotatingsaid roller continually, means for heating said container and means forguiding said gripper over said roller to cause the articles containedtherein to remain in contact with said roller over a predeterminedlength of its periphery and means for supplying heat directly to thearticle portions to be soldered during and subsequently to the solderingoperation.

6. In a machine for soldering articles together, grippers for holdingthe articles in soldering position, a co'nveyer for supporting andconveying, said grippers in a prescribed path and a solder applyingdevice located in the path of the articles, said device comprising asolder container, a roller journalled therein and protruding with aportion of'its periphery beyond the container, edge, means for rotatingsaid roller continually means for heating said container,

and means for guiding said grippers over sald roller to cause theartlcles contained I heating said article portions during and a suitabletime after the soldering operation.

HERMAN O. BOEHME-

